Commit 260442cc authored by Paul Cercueil's avatar Paul Cercueil Committed by Jonathan Cameron
Browse files

iio: adc: ad7091r5: Add scale and external VREF support 



The scale can now be obtained with the "in_voltage_scale" file.
By default, the scale returned corresponds to the internal VREF of 2.5V.

It is possible to use an external VREF (through the REFIN/REFOUT pin of
the chip), by passing a regulator to the driver. The scale will then be
calculated according to the voltage reported by the regulator.

Signed-off-by: default avatarPaul Cercueil <paul.cercueil@analog.com>
Co-developed-by: default avatarBeniamin Bia <beniamin.bia@analog.com>
Signed-off-by: default avatarBeniamin Bia <beniamin.bia@analog.com>
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent ca693001

drivers/iio/adc/ad7091r-base.c

+38 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#include <linux/interrupt.h>

#include <linux/module.h>

#include <linux/regmap.h>

#include <linux/regulator/consumer.h>



#include "ad7091r-base.h"
@@ -42,6 +43,7 @@ enum ad7091r_mode { 
struct ad7091r_state {

	struct device *dev;

	struct regmap *map;

	struct regulator *vref;

	const struct ad7091r_chip_info *chip_info;

	enum ad7091r_mode mode;

	struct mutex lock; /*lock to prevent concurent reads */
@@ -141,6 +143,21 @@ static int ad7091r_read_raw(struct iio_dev *iio_dev, 
		ret = IIO_VAL_INT;

		break;



	case IIO_CHAN_INFO_SCALE:

		if (st->vref) {

			ret = regulator_get_voltage(st->vref);

			if (ret < 0)

				goto unlock;



			*val = ret / 1000;

		} else {

			*val = st->chip_info->vref_mV;

		}



		*val2 = chan->scan_type.realbits;

		ret = IIO_VAL_FRACTIONAL_LOG2;

		break;



	default:

		ret = -EINVAL;

		break;
@@ -183,6 +200,13 @@ static irqreturn_t ad7091r_event_handler(int irq, void *private) 
	return IRQ_HANDLED;

}



static void ad7091r_remove(void *data)

{

	struct ad7091r_state *st = data;



	regulator_disable(st->vref);

}



int ad7091r_probe(struct device *dev, const char *name,

		const struct ad7091r_chip_info *chip_info,

		struct regmap *map, int irq)
@@ -216,6 +240,20 @@ int ad7091r_probe(struct device *dev, const char *name, 
			return ret;

	}



	st->vref = devm_regulator_get_optional(dev, "vref");

	if (IS_ERR(st->vref)) {

		if (PTR_ERR(st->vref) == -EPROBE_DEFER)

			return -EPROBE_DEFER;

		st->vref = NULL;

	} else {

		ret = regulator_enable(st->vref);

		if (ret)

			return ret;

		ret = devm_add_action_or_reset(dev, ad7091r_remove, st);

		if (ret)

			return ret;

	}



	/* Use command mode by default to convert only desired channels*/

	ret = ad7091r_set_mode(st, AD7091R_MODE_COMMAND);

	if (ret)

drivers/iio/adc/ad7091r-base.h

+1 −0
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ struct ad7091r_state; 
struct ad7091r_chip_info {

	unsigned int num_channels;

	const struct iio_chan_spec *channels;

	unsigned int vref_mV;

};



extern const struct regmap_config ad7091r_regmap_config;

drivers/iio/adc/ad7091r5.c

+5 −0
Original line number Diff line number Diff line
@@ -35,10 +35,13 @@ static const struct iio_event_spec ad7091r5_events[] = { 
#define AD7091R_CHANNEL(idx, bits, ev, num_ev) { \

	.type = IIO_VOLTAGE, \

	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \

	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \

	.indexed = 1, \

	.channel = idx, \

	.event_spec = ev, \

	.num_event_specs = num_ev, \

	.scan_type.storagebits = 16, \

	.scan_type.realbits = bits, \

}

static const struct iio_chan_spec ad7091r5_channels_irq[] = {

	AD7091R_CHANNEL(0, 12, ad7091r5_events, ARRAY_SIZE(ad7091r5_events)),
@@ -57,11 +60,13 @@ static const struct iio_chan_spec ad7091r5_channels_noirq[] = { 
static const struct ad7091r_chip_info ad7091r5_chip_info_irq = {

	.channels = ad7091r5_channels_irq,

	.num_channels = ARRAY_SIZE(ad7091r5_channels_irq),

	.vref_mV = 2500,

};



static const struct ad7091r_chip_info ad7091r5_chip_info_noirq = {

	.channels = ad7091r5_channels_noirq,

	.num_channels = ARRAY_SIZE(ad7091r5_channels_noirq),

	.vref_mV = 2500,

};



static int ad7091r5_i2c_probe(struct i2c_client *i2c,